The present invention relates to a method and a device to measure the impedance of radioelectric antennas carrying out high-frequency transmission in a broad bandwidth.
The use of a broadband antenna in transmission requires the positioning of a matching device between the transmitter and the antenna in order to match the output impedance of the amplifier that powers the antenna with the characteristic impedance of the antenna.
The matching device is usually controlled by successive approximations with checks being made each time on the standing-wave ratio and the phase of the signal at the input of the device. The matching is done when the standing-wave ratio has descended below a given threshold value.
The execution of such a process requires a large number of iterative operations that take time and delay the transmission of the useful signal accordingly.
In addition, the devices implemented to measure the standing-wave ratio are rudimentary and, since they are sized in order to work in broad frequency bands, transmitters that are geographically nearby can always disturb the measurements because of their lack of selectivity.